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<div class="titlepage"><div><div><h4 class="title">
<a name="boost_regex.ref.internals.uni_iter"></a><a class="link" href="uni_iter.html" title="Unicode Iterators">Unicode Iterators</a>
</h4></div></div></div>
<h5>
<a name="boost_regex.ref.internals.uni_iter.h0"></a>
          <span class="phrase"><a name="boost_regex.ref.internals.uni_iter.synopsis"></a></span><a class="link" href="uni_iter.html#boost_regex.ref.internals.uni_iter.synopsis">Synopsis</a>
        </h5>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">regex</span><span class="special">/</span><span class="identifier">pending</span><span class="special">/</span><span class="identifier">unicode_iterator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></pre>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U16Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint16_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u32_to_u16_iterator</span><span class="special">;</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u16_to_u32_iterator</span><span class="special">;</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U8Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint8_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u32_to_u8_iterator</span><span class="special">;</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u8_to_u32_iterator</span><span class="special">;</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">utf16_output_iterator</span><span class="special">;</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">utf8_output_iterator</span><span class="special">;</span>
</pre>
<h5>
<a name="boost_regex.ref.internals.uni_iter.h1"></a>
          <span class="phrase"><a name="boost_regex.ref.internals.uni_iter.description"></a></span><a class="link" href="uni_iter.html#boost_regex.ref.internals.uni_iter.description">Description</a>
        </h5>
<p>
          This header contains a selection of iterator adaptors that make a sequence
          of characters in one encoding "look like" a read-only sequence
          of characters in another encoding.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U16Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint16_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u32_to_u16_iterator</span>
<span class="special">{</span>
   <span class="identifier">u32_to_u16_iterator</span><span class="special">();</span>
   <span class="identifier">u32_to_u16_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span>

   <span class="comment">// Other standard BidirectionalIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          A Bidirectional iterator adapter that makes an underlying sequence of UTF32
          characters look like a (read-only) sequence of UTF16 characters. The UTF16
          characters are encoded in the platforms native byte order.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u16_to_u32_iterator</span>
<span class="special">{</span>
   <span class="identifier">u16_to_u32_iterator</span><span class="special">();</span>
   <span class="identifier">u16_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span>
   <span class="identifier">u16_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">start_range</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">end_range</span><span class="special">);</span>

   <span class="comment">// Other standard BidirectionalIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          A Bidirectional iterator adapter that makes an underlying sequence of UTF16
          characters (in the platforms native byte order) look like a (read-only)
          sequence of UTF32 characters.
        </p>
<p>
          The three-arg constructor of this class takes the start and end of the
          underlying sequence as well as the position to start iteration from. This
          constructor validates that the underlying sequence has validly encoded
          endpoints: this prevents accidentally incrementing/decrementing past the
          end of the underlying sequence as a result of invalid UTF16 code sequences
          at the endpoints of the underlying range.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U8Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint8_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u32_to_u8_iterator</span>
<span class="special">{</span>
   <span class="identifier">u32_to_u8_iterator</span><span class="special">();</span>
   <span class="identifier">u32_to_u8_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span>

   <span class="comment">// Other standard BidirectionalIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          A Bidirectional iterator adapter that makes an underlying sequence of UTF32
          characters look like a (read-only) sequence of UTF8 characters.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">u8_to_u32_iterator</span>
<span class="special">{</span>
   <span class="identifier">u8_to_u32_iterator</span><span class="special">();</span>
   <span class="identifier">u8_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span>
   <span class="identifier">u8_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">start_range</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">end_range</span><span class="special">);</span>

   <span class="comment">// Other standard BidirectionalIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          A Bidirectional iterator adapter that makes an underlying sequence of UTF8
          characters look like a (read-only) sequence of UTF32 characters.
        </p>
<p>
          The three-arg constructor of this class takes the start and end of the
          underlying sequence as well as the position to start iteration from. This
          constructor validates that the underlying sequence has validly encoded
          endpoints: this prevents accidentally incrementing/decrementing past the
          end of the underlying sequence as a result of invalid UTF8 code sequences
          at the endpoints of the underlying range.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">utf16_output_iterator</span>
<span class="special">{</span>
   <span class="identifier">utf16_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">BaseIterator</span><span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
   <span class="identifier">utf16_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">utf16_output_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">);</span>
   <span class="identifier">utf16_output_iterator</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">utf16_output_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">);</span>

   <span class="comment">// Other standard OutputIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          Simple OutputIterator adapter - accepts UTF32 values as input, and forwards
          them to <span class="emphasis"><em>BaseIterator b</em></span> as UTF16. Both UTF32 and UTF16
          values are in native byte order.
        </p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">utf8_output_iterator</span>
<span class="special">{</span>
   <span class="identifier">utf8_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">BaseIterator</span><span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
   <span class="identifier">utf8_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">utf8_output_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">);</span>
   <span class="identifier">utf8_output_iterator</span><span class="special">&amp;</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">utf8_output_iterator</span><span class="special">&amp;</span> <span class="identifier">that</span><span class="special">);</span>

   <span class="comment">// Other standard OutputIterator members here...</span>
<span class="special">};</span>
</pre>
<p>
          Simple OutputIterator adapter - accepts UTF32 values as input, and forwards
          them to <span class="emphasis"><em>BaseIterator b</em></span> as UTF8. The UTF32 input values
          must be in native byte order.
        </p>
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<td align="right"><div class="copyright-footer">Copyright © 1998-2013 John Maddock<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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